Intermittent driving mechanism



Feb 21, 1967 K. R. SCHNEIDER INTERMITTENT DRIVING MECHANISM 4 Sheets-Sheet l Filed April 28, 1965 INVENTOR ATTORNEY Feb. 21, 1967 K. R. SCHNEIDER 3,305,056

INTERMITTENT DRIVING MECHANISM Filed April 28, 1965 4 Sheets-Sheet 2 INVENTOR Feb. 2l,

Filed April 28, 1965 K. R. SCHNEIDER INTERMITTENT DRI VING MEGHANI SM HHH IHN: Il R m L ,I

"U :449' H1 l? l i! 5l Q 1': L, i )l E@ 4 Sheets-Sheet 5 Hull!" ATTORNEY Feb- 21, 1967 K. R. SCHNEIDER INTERMITTENT DRIVING MECHANISM 4 Sheets-Sheet 4 Filed April 28, 1965 A f. A r

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United States Patent O 3,305,056 INTERMITTENT DRIVING MECHANISM Kurt Rudolf Schneider, 4 .Iuliand St., Bainbridge, N.Y. 13733 Filed Apr. 28, 1965, Ser. No. 451,563 6 Claims. (Cl. 192-33) This invention relates to improvements in power drives for label applying machines of the type exemplified in my prior Patents Nos. 2,754,022, 2,907,567 and 3,010,- 864, and my -application Serial No. 80,778, filed Ianuary 5, 1961, now Patent No. 3,252,849, and more especially to an improved clutch mechanism incorporated in said power drive means for transmitting drive to the various instrumentalities of such a machine which are required to be driven intermittently throughout definite cycles of motion including, without limitation, the label sheet-topunch mechanism feed means and the punch mechanism which functions to sever a succession of individual labels from the label sheet feeding to same and to apply the individual labels to moistened areas of a succession of articles to be labeled, i.e. mailing pieces such as envelopes, postcards and the like, which are positively `advanced thereto by a so-called conveyor belt stage.

As explained in my Patent No. 2,915,160, dated December 1, 1959, directed to an earlier design of a clutch mechanism for a label applying machine as aforesaid, the clutch mechanism suited to the needs of such Ia machine must satisfy rigid requirements not only as respects the means employed for smoothly engaging and disengaging the clutch elements themselves but also as respects the means to latch up the clutch, i.e. to stop and hold the driven clutch head in a fixed angular stop position after it has completed its cycle of motion. While, generally speaking, the clutch mechanism according to my aforesaid Patent No. 2,915,160 performed satisfactorily, it was soon realized that the initial fabrication cost thereof was high, and continuing experience with labeling machines using same furthermore revealed that the stoppin means employed therein to stop and hold the driven clutch lhead assembly in the fixed angular stop position was a source of trouble in that the stop pin was likely to stick and, when such occurred, it could either jam the clutch or not stop the driven clutch head assembly as intended. Sluch in turn resulted not only in improper and sometimes messy labeling but also usually involved substantial expense in correcting the malfunctioning of the stop pin, since this correction could be performed only by specially trained servicing personnel. In short, practical considerations gained through experience with the prior clutch mechanism of my Patent No. 2,915,160 indicated the need of a re-design thereof.

Stated broadly, a major object of the present invention is the provision of a clutch mechanism of the general type and serving the same overall purpose as that disclosed in my prior Patent No. 2,915,160 but which is of improved and simplified designfhaving the advantage of low first cost even when manufactured in small quantities and giving dependable, trouble-free operation.

A more particular object of the invention is the provision of a clutch mechanism of the stated character which incorporates improved latch-up or power stop means, as compared to that disclosed in my prior Patent No. 2,915,- 160, for effecting stopping of the driven clutch head 'assembly thereof at a fixed angular position as determines the end of its cycle of movement (or cycles if such are called for) and which is the same position throughou repeated cycles of clutch operation.

The above and other objects and features of advantage of a power drive for label applying machines, `and particularly of a clutch mechanism for incorporation therein, as contemplated and provided by the present invention will appear from the following detailed description Y' of a preferred physical embodiment thereof shown in the accompanying drawings, wherein FIGS. 1 and 2 are generalized top plan and side elevational views of a label applying machine of the type for which t-he improved power drive and clutch mechanism of the present invention are adapted, of which FIG. 2 is taken from the label sheet feed-in side of said machine, said views further generally illustrating in broken lines the position of the improved clutch mechanism in such a machine and the drive train between the clutch and punch mechanisms;

FIG. 3 is a sectional view taken through FIG. 2 on a horizontal plane located just below the top plate and front table of the label applying machine therein shown and which illustrates .generally the lay-out of the power drive means including the improved clutch mechanism within the base of said machine;

FIG. 4 is an enlarged part-sectional side elevation of the improved clutch mechanism and its power stop means according to the invention, with certain parts being shown in conventional form;

FIG. 5 is a section taken along line 5 5 of FIG. 4;

FIG. 6 is a perspective view showing the drive connection between the main drive shaft and two instrumentalities of a label applying machine generally according to my aforesaid Patent No. 2,754,022, which are required to be driven intermittently throughout definite cycles of motion, which is provided by the improved clutch mechanism of the present invention;

FIGS. 7 and 8 are side and front views showing in detail the form and configuration of the sleeve element of the driven clutch head assembly according to the present invention; and

FIG. 9 is a section taken along line 9 9 of FIG. 4, illustrating in detail the simplified adjustable limit stop means for the trip lever forming a part of the clutchmechanism operating and power-stop means of the invention.

Referring to the drawings in greater detail, FIGS. 1 and 2 depict a label applying machine generally according to my aforesaid Patent No, 2,750,022 and later filed application Serial No. 80,778, for which the power drive means incorporating the improved clutch mechanism and its power stop means of the invention was designed and has particular utility. Using insofar as is possible the same reference characters and/ or numerals as were used to designate corresponding parts in the machine shown in my aforesaid patent and application, reference character BH designates a `base having a top plate TP over which a label sheet L, on which rests a label-sheet pres- 2 s-ure plate SHQ mounting a label sensing switch LLS,

plates GP between which a stack E of articles to be labeled, i.e. mailing pieces such as envelopes, postcards, etc., may be placed, said table also mounting a forward guide plate GF against which the forward edges of the mailing pieces of the stack are held while a lower mailing piece is being Withdrawn for subsequent advancement to the punch housing.

A machine power drive is provided, such by reference to FIG. 3 being substantially enclosed within the base housing BH and comprising an electric driving motor EM which drives through a speed reducer SR, one-way ball clutch ORC, timing belt TB-l and sprocket pulley SP, a main drive shaft AC mounting a bevel gear 23 in mesh with a bevel gear 24 fast on a primary feed-roll shaft 25 which extends transversely across the base housing. At its far end, said shaft 25 mounts a driver sprocket pulley 30 driving a timing belt T13-2 which in turn drives a sprocket pulley 33 powering the shaft 37 having universal joints 36, 38 at its ends and which provides a driving connection for the continuously driven conveyor-belt stage generally designated S serving to advance the mailing pieces to be labeled, which are fed in beneath the under surface of the top plate TP, to a cyclically operable, reciprocating punch unit ram in the aforesaid punch housing PH and which operates through an aperture in said top plate, all as described in my aforesaid Patent No. 2,754,222 and application Serial No. 80,778. Since said conveyor-belt stage S and said punch mechanism per se form no part of the present invention, and furthermore because earlier designs thereof are described in my prior Patents Nos. 2,754,222 and 3,010,864 and my aforesaid application Serial No. 80,778, and improved designs thereof are disclosed in detail and claimed in my applications Serial No. 451,460 and Serial No. 451,469, respectively, filed under even date herewith, to which reference may be had, if needed, no further descriptions thereof are here given.

However, it is here explained that said conveyor-belt stage S is a component of the overall article feed-through means of my aforesaid concurrently filed application Serial No. 451,460, which also includes article run-out means for receiving the labeled articles (mailing pieces) discharging from the conveyor-belt stage proper and discharging same from the machine, and which is also con tinuously driven by the power drive means of the invention. Illustratively, such run-out means comprises the two rubber-coated run-out rollers 200, 202 disposed forwardly of said stage S and being mounted for turning movement about the axes of their longitudinally spacedapart, transversely extending carrying shafts and for rocking motion in unison about a transverse axis disposed intermediate said roller axes. Said rollers are powered by a long O-belt 212 extending between an O-belt drive pulley 33p atlxed to and turning with the aforesaid sprocketpulley 33 and O-belt pulleys 200p, 202p fast on the roller shafts.

The aforesaid shaft 25 operates within a hollow sleeve shaft 25a, upon which are affixed the primary feed rollers EFR, the shaft 2S driving the sleeve shaft by means of an overrunning clutch 2519. As explained in my aforesaid application Serial No. 80,778, the normal peripheral speed of the feed rollers EFR, when the latter are driven by the shaft 25a, is less than that at which the twin conveyor belts of the stage S operate so that, when picked up by the conveyor belt stage, the articles are advanced more rapidly than while being advanced by said feed rollers EPR, the over-running clutch 25b permitting such action by enabling the sleeve shaft 25a to overrun its driving shaft 25.

Gears 25C, 25d, 25e which are powered by said shaft 25 drive an article feeding roll 25) through the clutch 25g, assuming engagement of the latter. Roll 25j receives one end of an endless feed-in belt 25h (FIGS. 1 and 3) which at its free end is carried by a wobble pulley 251' on a shaft mounted beneath the table plate TR and whose upper and lower flights are positionally controlled intermediate their respective lengths by an idler roller 25j. As such an article (mailing piece) feed-in means is fully disclosed in my Patent No. 2,907,567, reference may be had thereto for further details.

As also shown in FIG. 3, a rock shaft 40 has the articlecontrolling feed lingers EFF affixed thereon, which are raised when said shaft is rocked in proper direction by electromagnetic means (not shown) and which when so raised function to prevent mailing-piece advancement. Reference may also be had to my aforesaid Patent No. 2,907,567 for further details on the structure and operation of said feed-restraining fingers EFF.

Said drive shaft AC also drives, through a clutch mechanisrn generally designated CM with which the present invention is largely concerned, the various instrumentalities of the labeling machine required to be driven intermittently throughout one or more definite cycles of rotation, such instrumentalities being the punch mechanism (ram) contained in the aforesaid punch housing PH and the label-sheet feed means. Also to be included in this category is the envelope-moistening means EM (FIG. 1), although such in fact is driven off the punch mechanism. More particularly and now referring to FIGS. 4-6 inclusive, the main drive shaft AC, which is shown to be supported adjacent its driving-motor end in a sleeve bearing 50 carried by a bearing stand 52, mounts adjacent said stand a driving clutch head 54 and a driven clutch head assembly 56. The driving head S4 is shown to have the form of a simple bushing element provided on its end adjacent the driven clutch head assembly with driving teeth 54a, and it is pinned or otherwise made fast to said drive shaft AC for rotation therewith. The driven clutch head assembly 56 illustratively comprises an assembly of a relatively elongated, hardened steel sleeve .58 having end portions of different diameter, the larger-diameter end portion being provided with clutch teeth 58a for engagement with the aforesaid clutch teeth 54a, and a gear 60 fitted to the smaller-diameter end portion of said sleeve which is disposed remote from said driving head 54. Preferably, said gear is secured in a fixed angular position with respect to the sleeve, as by head screws 62 (FIG. 6), and against the relatively outer radial plane face of a radially projecting flange 64 with which the sleeve 15S is also provided and which separates the larger-and smaller-diameter end portions thereof. The opposite or innerradial face of said flange 64, that is, the face adjacent said driving head, is provided along its outer edge or rim portion with a cam track CT whose configuration will be later described in detail.

Referring to FIG. 4, the sleeve component 58 of the driven head assembly 56 has fitted into the opposite endsl of its bore the sleeve bearings a, 7Gb, providing for frictionless rotation of the drive shaft AC with respect thereto when the clutch teeth are disengaged and said driven head assembly is held against rotation. As is conventional in clutches of this character, said driven clutch head assembly is normally maintained in a disengaged position but is axially slidable on the drive shaft AC to an engaged position by a clutch spring. Illustratively, the clutch spring herein employed is a coil spring 72 encir cling the drive shaft and being held in compression between spaced bushings 74a, *Mb provided with spring-end seating means, of which the bushing 74a is slidable on the drive shaft and presses against the sleeve 58 and the bushing 74h is affixed to the drive shaft and thus serves as the reaction member for said spring.

The means employed to maintain the driven clutch head assembly 56 in its neutral or normally disengaged position against the bias of the spring '72 comprises a ballbearing mounted roller-type follower 76 turning on a piu 7 8 affixed to and projecting upwardly from 'the upper edge of the operating, i.e. longer, end of the trip lever 8l), which roller, in the raised position of said lever operating end, is disposed at 'a level as to engage :against the aforesaid cam track CT on the radial face of the flange 64 of the driven clutch-head sleeve 58. As seen in FIGS. 4 and 6 in particular, said trip lever 80 is pivotally connected by means lof a pivot pin `S2 to the forked upper end of :an upright post 34 affixed to the machine base, the dis-position of said post and pivot pin being such that the trip ilever is located immediately below and is rockable in the vertical plane of said drive shaft AC. A tension spring 86 connected at its one end to a low point on the upright post 84 and at its other end to a hook provided on the shorter end of the trip lever, i.e. the end'remote from its aforesaid operating end, acts normally to maintain said operating end in its full-raised position, -as such is determined by engagement of said operating end against the bottom lof a slot 88a provided in an inverted U-shaped stop member 88 secured in a desired position of vertical adjustment to a side face `of the aforesaid bearing stand 52. By virtue of the trip lever 80 being confined near its shorter end between the arms or forks of the post 84 and at its other end between the vertical sides of the slot 88a provided in said stop member 88, it is effectively restrained against any undesirable sidewise motion.

Downward motion of the operating end of said trip lever 80 against the force of the tension spring 86 occurs upon energization of the coil of a Vsolenoid struc-ture SS affixed to the machine base below said operating end and whose armature 90 is connected to said operating end as by means of a connecting pin 92. When the solenoid coil is energized, the operating end of the trip lever 80 is lowered vby the pull of the coil on the armature 90, and accordingly the roller 76 carried by the trip llever moves downwardly from engagement with the aforesaid cam track CT provided -along the peripheral edge of the driven head ange 64, whereupon the clutch head assembly 56, being now free to move axially toward the clutch driving head 56, does so under the force of the clutch spring 72, to an axial position in which the clutch teeth 54a, 58a ful-ly engage.

The aforesaid cam track CT is specially designed and formed to suit the aims and purposes of the present invention. More particularly, the cam track is machined or otherwise provided in the peripheral edge portion of said flange 64 of the driven head along a radius thereof as insures its engagement by the roller 76 when the latter is in its full-raised iposition. Also, as will be seen in FIGS. 7 and 8, said cam track extends throughout an arc of approximate-ly 270 as a roller-track portion a disposed in the same radial plane, and throughout its remaining 90 (i) arcuate length, it is formed with an axially projecting cam rise which includes a short arcuate-length inclined ramp portion b leading to a recess portion c, which latter is bounded on its side opposite that to which said ramp portion connects by a high-rise -portion d serving as a roller-barrier portion. Referring to the recess portion c of the rise in particular, such preferably takes the form of an arcuate mill-cut cavity of radius corresponding to that of the cam-track engaging roller 76 and which extends inwardly from the outer peripheral edge of said flange 64 for an appreciable distance along a radius thereof and terminates in a plane inner-end wall c1. The purpose of said mill-cut cavity or recess c is to provide a `seat to which the `roller 76 may be positively held at the end of one complete revolution of the driven clutch head assembly 56, if called upon to do so.

According -to a further feature of the invention, the stop pin means employed in the clutch mechanism of my aforementioned Patent No. 2,915,160 to latch up the clutch in a fixed angular power-stop position when it has cornpleted its cycle of motion is done away with entirely. Instead, there is provided a second ball-bearing mounted roller 96 disposed in the same horizontal plane as the cam-track engaging roller 76 and turning on the axis of a pin 98 also affixed to and extending upwardly from the upper edge of the trip lever 80 and being located in predetermined spaced relation to said cam-track engaging roller as positions it (said roller 96) to bear against the fully exposed radial plane surface of the gear 60, that is. the relatively outer face of said gear which is disposed opposite the face of said flange 64 to which the -gear is secured as aforesaid, when the roller 76 seats in the recess portion c of the cam rise. More particularly, the axis of the pin 98 on which said latter roller 96 turns is spaced from the turning axis of the cam-track engaging roller 76 a predetermined fixed distance such that the two closest points on the peripheries of said rollers are spaced apart a distance equal to the distance tbetween the lowest point on the arc of said mill-cut recess portion c and said exposed radial plane face -of the gear 60.

Such arrangement provides that, upon the solenoid SS being deenergized following each period of clutch engagement and the trip leve-r 80 moving in clockwise direction (FIG. 4) about the axis of its mounting pin 82 under the bias of the tension spring 86 acting on the shorter end of said lever, the roller 76 will move upwardly into engagement with the aforesaid cam track CT, and similarly the second roller 96 carried by the trip lever will move upwardly to the level of the peripheral edge portion of the exposed radial plane face of the gear 60 of the driven clutch head assembly 56. Assuming said driven head assembly including the gear to be still rotating with some momentum at the instant of solenoid deenergization, said driven head assembly will ultimately arrive at an angular position in which the cam-engaging roller 76 will seat in the cam track Arecess c. At the `same instant, the roller 96, consequent to its predetermined spacing from the roller 76 as above, will engage the plane outer face of the gear 60 and, when such occurs, further rotation of the driven clutch head assembly is positively prevented by the conjoint action of both said -rollers 76 and 96 on the cam track CT and gear face, respectively, which action is that of preventing the further angular movement of said flange 64 (and thereby the entire driven head assembly 56) required to unseat roller 76 froml the cam-track recess c.

FIG. 6 illustrates schematically the plural drive trains between the drive shaft AC and the punch and the labelsheet feed mechanisms, in which the above described clutch mechanism CM functions as an intermittently operating power transfer connection. More particularly, the aforesaid gear 60 drives a gear 110 mounted on a stub shaft 111, which gear meshes with a gear 112 mounted on a cross shaft 113 extending to the punch mechanism contained in the punch housing PH. Preferably, all three said gears are helical or skewgears whose teeth are arranged with respect to yone another as disclosed in my aforesaid Patent No. 2,915,160, thus to reduce shock in starting and also to insure smoothness in stopping of the drive trains under load. The gear drives a pitmau 115 connected to a cross head 116 to which is aixed the shuttle barsy 118, having upwardly protruding labelsheet feed teeth or projections 122 thereon. Thus, rotation of the gear 110 is translated into reciprocatory motion of said shuttle bars and step-by-step feed of the label sheet L (FIG. l) to the punch mechanism the distance of one label, all as described in my aforesaid Patent No. 3,010,864.

As generally indicated in broken lines (FIG. 1), the cross shaft 113 extends crosswise of the machine top plate TP to near the punch housing PH where it mounts a sprocket pulley 124 driving a timing belt 125. Said belt is preferably trained Iover an idler sprocket pulley 126 functioning as a belt-tightening means, and thence about the sprocket pulley 127, thereby to drive the latter. Said pulley 127 preferably forms a component of the punch unit drive assembly described and claimed in my aforesaid concurrently led application Serial No. 451,469, directed to the punch mechanism. Thus, rotation of the gear 60 is also translated into reciprocatory motion of the punch unit of said punch mechanism.

The clutch-assembly including gear 60 is also shown to be in mesh with a helical gear 130 which drives the timing cams 1'70a, 170b which in Iturn operate the cam switches CSa, CSb (FIG. 3). However, since said cams and timing sun'tches, together with said label-sensing switch LSS, and an article, i.e. mailing-piece, sensing switch (not shown) associated with the aforesaid conveyor stage S are each components of the machine control and/ or cycling means with which the present inventi-on is not specifically concerned, and as said components and their yoperation are described in detail in my aforesaid application Serial No. 80,778, no further description thereof or of the circuitry in which they are connected is herein given. Nonetheless, it will be helpful to an understanding of the present invention toy state that energization of the clutch disengaging solenoid SS occurs and can occur only if an article, i.e. a mailing piece, is being properly advanced by the conveyor-belt stage to the punch mechanism and a label is present for application to said mailing piece. If both such conditions are not satisfied, the machine will not operate except under manual control exercised through drive shaft extension AC-l and hand knob ACK, as, for example, when it is desired to make sure -of accurate label feed and/ or accurate article feed prior to starting the driving motor EM.

Without further analysis, it will be appreciated that the power drive and clutch mechanism described and illustrated herein incorporate numerous improvement features as compared to the prior designs thereof which are disclosed in my aforesaid patents and application Serial No.

80,778. More particularly, timing belts and toothed pulleys have largely supplanted gear-drive connections. The drive means of the invention has been expanded so as to extend to the run-out yrollers for effecting positive runout from the machine of the labeled articles discharging from the conveyor belt stage S. The provision of the over-running (one way) ball clutch ORC in the drive train between motor EM and drive shaft AC is notable, in that such permits testing of the machine as may be necessary with power turned off, by hand-turning said drive shaft via the drive shaft extension AC-l and hand knob ACK (FIG. 1) without havin-g to rst overcome the resistance of the motor and the gear drive previously interposed between motor and drive shaft.

The invention also provides an effective latch-up or power stop means for a clutch mechanism of the type employing roller-type follower and cam-track means for disengaging the driven from the driving head elements thereof, upon the driven head assembly completing a predetermined cycle or cycles of motion. While said power stop means operates on the principle of driving a wedge between two nen-separable abutment surfaces, the fact that according to the invention said surfaces are the outer peripheries of two rotatable rollers results in an effective power stop just as if said surfaces were fixed abutments such as studs, but at the same time -in said means operating with a feather touch and with no likelihood of becoming permanently wedged or jammed.

Moreover, it will be appreciated that clutch mechanism according to the invention considered as a whole is characterized by extremely simple construction making for trouble-free operation. This simplified construction results in the present clutch mechanism being substantially less expensive in fabrication than the clutch mechanism disclosed in my Patent No. 2,915,160, for example, since .in addition to eliminating the expensive-to-assemble and difficult-to-service stop-pin type of power stop means inco-rporated in the clutch mechanism according to said patent, it eliminates one of the two trip-lever mounting posts employed in the prior clutch mechanism and it additionally incorporates a simplified upper limit stop for the trip lever, as compared to that employed in the prior clutch mechanism.

As many changes could be made in carrying out the above constructions without departing from the scope of the invention, it is intended that all matter contained in the above description or shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense.

I claim:

1. A clutch mechanism comprising a rotatable driving head, a coaxially related rotatable driven head assembly axially slidable relative to said driving head between a first position of engagement therebetween and a second position of disengagement, said driven head assembly including a radially outwardly directed peripheral liange, said flange having axially oppositely directed first and second faces, said first face having a cam track including high and low cam track portions, the high cam track portion of said cam track being spaced a predetermined distance from said second face as measured along a line parallel to the axis of said driving head and driven head assembly, means for relatively moving said driving head and driven head assembly toward said first position, cam follower means cooperative with said cam track for urging said dri-ven head assembly toward said second position, means movable to a position adjacent said second face in aiignrnent for axial abutment therewith thereby limiting the movement of said driven head assembly toward said second position, and said cam follower and movable means being spaced from each other a constant distance as measured parallel to the axis of said driving head and said driven head assembly, and said constant distance is less than said predetermined distance whereby rotation of said driven head assembly is stopped by the clamping engagement of said first and second faces between said cam follower and said movable means.

2. The clutch mechanism as defined in claim 1 wherein said cam follower is of a predetermined external diameter, said cam track includes an intermediate cam track portion between said high and low cam track portions, and said intermediate cam track portion is complementary contoured to the configuration of said cam follower whereby the latter seatingly engages said intermediate cam track portion in the p-osition of clamping engagement of said first and second faces.

3. The clutch mechanism as defined in claim 2 wherein said second face is completely uniplanar and is disposed in a plane generally normal to the axis of said driving head and driven head assembly.

4. The clutch mechanism as defined in claim 2 wherein said movable means is defined in part by a roller having a peripheral surface disposed for engagement with said second face, said cam follower and roller are carried by common means, and means for selectively moving said common means to disengage said cam follower and roller from the respective first and second faces to permit subsequent rotati-on of said driven head assembly.

5. The clutch mechanism as defined in claim 3 wherein said movable means is defined in part by a roller having a peripheral surface disposed for engagement with said second face, said cam follower and roller are carried by common means, and means for selectively moving said common means todisengage said cam follower and roller from the respective first and second faces to permit subsequent rotation of said driven head assembly.

6. A clutch mechanism comprising a rotatable driving head, means for driving said driving head, a coaxia'lly related rotatable driven head assembly axially slidable toward and away from said driving head between a first position of engagement therebetween and a second position of disengagement, said driven head assembly including a radially outwardly directed peripheral flange, said flange having axially oppositely directed first` and second faces, said first face having a cam track including high, intermediate and low cam track portions, means for normally biasing said driven head assembly toward said driving head to effect engagement therebetween, a cam follower cooperative with said cam track for urging said driven head assembly toward said second position, a roller normally positioned adjacent said second face in alignment for axial abutment therewith thereby limiting Vthe movement of said driven head assembly toward said second position, said cam follower and roller being carried by common means, means for selectively moving said common means to effect disengagement of said cam follower and roller relative to the respective first and second faces whereby said driven head `assembly is slidable toward said driving means, said cam follower being of a predetermined external diameter, and said intermediate cam track portion is complementary contoured to the configuration of said cam follower whereby the latter seatingly engages said intermediate cam track portion at the time said roller contacts said second face whereby rotation of said driven head assembly is prevented due to the clamping engagement of said first and second faces between the respective cam follower and roller.

(References on following page) 9 10 References Cited by the Examiner 2,901,069 8/ 1959 Przysiecki 19233 2,915,160 12/1959 Schneider 192-33 X UNITED STATES PATENTS 3,164,233 1/1965 Swanson 192-33 8/1941 Davis 192-33 X 12/ i945 MiChClmIl 7%625 5 DAVID I. WILLIAMOWSKY, Primary Examiner. 10/ 949 Watson et all 74- 5 X 11/1954 Krom 74 625 A. T. MCKEON, Asslstant Exummer. 

1. A CLUTCH MECHANISM COMPRISING A ROTATABLE DRIVING HEAD, A COAXIALLY RELATED ROTATABLE DRIVEN HEAD ASSEMBLY AXIALLY SLIDABLE RELATIVE TO SAID DRIVING HEAD BETWEEN A FIRST POSITION OF ENGAGEMENT THEREBETWEEN AND A SECOND POSITION OF DISENGAGEMENT, SAID DRIVEN HEAD ASSEMBLY INCLUDING A RADIALLY OUTWARDLY DIRECTED PERIPHERAL FLANGE, SAID FLANGE HAVING AXIALLY OPPOSITELY DIRECTED FIRST AND SECOND FACES, SAID FIRST FACE HAVING A CAM TRACK INCLUDING HIGH AND LOW CAM TRACK PORTIONS, THE HIGH CAM TRACK PORTION OF SAID CAM TRACK BEING SPACED A PREDETERMINED DISTANCE FROM SAID SECOND FACE AS MEASURED ALONG A LINE PARALLEL TO THE AXIS OF SAID DRIVING HEAD AND DRIVEN HEAD ASSEMBLY, MEANS FOR RELATIVELY MOVING SAID DRIVING HEAD AND DRIVEN HEAD ASSEMBLY TOWARD SAID FIRST POSITION, CAM FOLLOWER MEANS COOPERATIVE WITH SAID CAM TRACK FOR URGING SAID DRIVEN HEAD ASSEMBLY TOWARD SAID SECOND POSITION, MEANS MOVABLE TO A POSITION ADJACENT SAID SECOND FACE IN ALIGNMENT FOR AXIAL ABUTMENT THEREWITH THEREBY LIMITING THE MOVEMENT OF SAID DRIVEN HEAD ASSEMBLY TOWARD SAID SECOND POSITION, AND SAID CAM FOLLOWER AND MOVABLE MEANS BEING SPACED FROM EACH OTHER A CONSTANT DISTANCE AS MEASURED PARALLEL TO THE AXIS OF SAID DRIVING HEAD AND SAID DRIVEN HEAD ASSEMBLY, AND SAID CONSTANT DISTANCE IS LESS THAN SAID PREDETERMINED DISTANCE WHEREBY ROTATION OF SAID DRIVEN HEAD ASSEMBLY IS STOPPED BY THE CLAMPING ENGAGEMENT OF SAID FIRST AND SECOND FACES BETWEEN SAID CAM FOLLOWER AND SAID MOVABLE MEANS. 